Modify the Filter policy: Scan request Whitelist | Connect request Whitelist and add the MAC address of the central device which you are interested in.to the white list So other central devices will not be able scan or connect to your peripheral. If you still not able to follow, refer the Whitelist Document at PSoC 101 documents.

I can't do this way. In my project any central would be able to scan and connect with peripheral but only during allowed time.

Is it possible to change Filter policy state at runtime ?

This way, peripheral would normally be at "Connect request Whitelist" mode and when pushing button permit to change Policy filter to allow connect any central and write this new central MAC to the whitelist.